Book light



FIG. 1 is a front view of a book light;

FIG. 2 is a rear view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a right side view thereof; and,

FIG. 7 is a front perspective view thereof.

The portions of the book light shown in broken lines form no part of the claimed design. 

CLAIM The ornamental design for a book light, as shown and described. 